Star India shuttler PV Sindhu had to dig deep to beat Denmark’s Line Christophersen in the women’s singles opening round, while HS Prannoy dished out a superlative display to stun World No. 6 Tien Chen Chou of Chinese Taipei in men’s singles of the Malaysia Masters here on Wednesday.

Sindhu, seeded sixth, had to toil for one hour and two minutes to get the better of Christophersen 21-13, 17-21, 21-18 and maintain her superiority over the World No. 33 Dane, who the Indian had defeated four times earlier.